JavaScript & DHTML Cookbook

Chapter 10. Page Navigation Techniques

Introduction

No web page is (or should be) an island. Just as there is a way to reach the page, so should there be one or more ways to navigate to other destinations, either within the same site or outside. The HTML hyperlink element—embedded in pages as the rather nondescript <a> tag—is the conventional, nonscripted way to provide a clickable avenue for the user to navigate to another page. But more sophisticated user interface designs frequently require Dynamic HTML to assist with the presentation of navigation options and the very act of navigating.

The location Object

Each window (and frame) object in every scriptable browser has a location object whose properties contain information about the URL of the page currently loaded into the browser. This is an abstract object, meaning that the object has no particular physical presence visible on the page—except perhaps the URL that appears in the browser’s Location or Address field. But the location object does not control what the user sees in the Location/Address field unless the browser succeeds in navigating to a page you assign to the location object.

Properties of the location object are read/write. The individual properties reveal components of the URL (and even the entire URL) of the loaded page. Without any restrictions to this information, however, scripts could spy on your browser activity without you knowing it. For example, imagine entering an unscrupulous web site that looks like ...